pacman::p_load(ggsignif, dplyr, magrittr, reshape, ggplot2)
ll <- "E:/projects/R_draw_sc/test/xianzhuxingboxplot/data/Diff.mat.txt" %>%
  read.delim() %>%
  melt() %>%
  select(2, 1) %>%
  set_colnames(c("exp", "group"))%$% unique(group) %>% as.character()
list <- list()
l <- ll %>% length()


for(i in 1:(l-1)){
  for(k in 1:(l-i)){
    list[[length(list)+1]] <- c(ll[i],ll[l+1-k])
  }
}